Machine for corrugating metal tubes



J. A. ZIEGLER MACHINE FOR CORRUGATING METAL TUBES se uo, 1929.

Filed April 17, 1925 6 Sheets-Sheet Jrwa Jam/HZ Zia gr aw me E w nk Set. 10, 1929. J. A. ZIEGLER MACHINE FOR CORRUGATING METAL TUBES I FiledApril 17, 1925 6 sheetsvsheet Joram Sept. 10, 1929- A J. A. ZIEGLER1,727,918

MACHINE FOR CORRUGATING METAL TUBES Filed April 17, 1925 6 Sheets-Sheet3 J. A. ZIEGLER MACHINE FOR CORRUGATING METAL TUBES Se t. 10, 1929.

6 Sheet S-Sheet 4 Filed April 1'7, 1925 P 1929- J. A. ZIEGLER MACHINEFOR CQRRUGATING METAL TUBES Filed April 17, 1925 6 Sheets-Sheet 5 p 10,1929- J. A. ZIEGLEIR 3,727,918

MACHINE FOR CORRUGATING METAL TUBES Filed April 17, 1925 6 Sheets-She t5 ifrfi U06 ,9 j 90.

fizz/67223 7 Patented Sept. 10, 192 9.

UNITED STATES PATENT-,OFFICE.

JOBAM A. ZIEGLER, OF LA CROSSE, WISCONSm', ASSIGNOB TO THE TBANECOMPANY,

OF LA CBOSSE, WISCONSIN, A CORPORATION. 1

MACHINE FOB CORRUGA'IING METAL TUBES.-

Application filed 4 m 17, 1925. Serial No. 23,792.

The invention relates to machines for corrugating metal tubes.

The object of the invention is to produce a device for formingtransverse corrugations 5 in metal tubes that shall expedite theformation of such corrugations, and give to them a superiorquality. Ithas been a usual practice in forming such corrugations, and'particularlyin forming such corrugations in thin walled tubes used in the productionof what is known in the art as flexible metal bellows, to roll or formby some other process applied to the metal, outwardly extending broadcorrugations, leaving therebetween uncorrugated portions; or by using aseries of corrugation forming rolls having a multiplicity of outwardlyextending corrugating beads, all formed in a unit, and operating as aunit to form a multiplicity of corrugations simultaneously. Such rollshave been applied to one face of the tube upon which the work is beingdone, accompanied by a companion roll applied to the opposite side ofthe tube, the beads of which are arranged to pass between the beads ofthe opposed roll. It has been believed that such corrugations could notbe formed unless there was a resistance upon one face of the tube to theoperation of the corrugation forming elements on the other side. But Ihave found a serious objection to either method, in that the firstmentioned process is slow and cumbersome, the corrugations being formedsingly, and fail to produce that uniformity in the shape of thecorrugations that is desirable, and at some period in the process offorming the corrugations, requires an additional operation to properlytreat the uncorrugated portion left between the corrugated portions.form all of the corrugations at once, there is found to be an unduestretching of the metal between the rolls, because the frictionengendered at the bends of the rollsprevents that lateral flow of themetal that tends to produce the best quality of corrugations. In myimproved process, I employ separate corrugating elements within andwithout the tube, each series of elements operating vdistinctivelyseparately from the longitudinally adjoining series, the inner seriesbeing also When it is attempted to separate from the outer series andlongitudinally spaced therefrom, I provide a longitudinal connectionbetween the inner and outerdevice thatcauses the elements to formsuccessively the corrugations intheir proper or-' der, one after theother. In this mode of forming the'corrugations'I find that I am able toproduce a more uniform seriesrof inner and outer corrugations than hasheretofore been the case, and the time involved in forming the entireseries of corru ations is but a fraction of the. time require byprevious methods.

The particular formzof the invention disclosed herein consists of innerand outer cylinders in fixed relation to each other in whlch are placedlongitudinal series of balls, 9. plurality of balls in eachcircumferential series,-

the inner series being .in'staggered' relation to the outer series, theouter balls being arranged to move radially inward against the outerface of the tube upon which the operav tion is being performed, toproduce inwardly entending corrugations, and the inner balls beingadapted to move outwardly against the inner face 'to form outwardlyextending corrugations, properly spaced from its adjacent corrugation asto form a continuous uninterrupted connection therewith. The outerseries of balls is operated by a ring movin longitudinall of thecylinder, to force t e balls inward y, and the inner cylinder'containing a thrust bar having an element that also successively movesupon the innerballs and forces them outwardl ,the inner and outercorrugations so forme having uninterrupted or unbroken connection witheach other. Inasmuch as it is desirable for some purposes-to have innercorrugations formed first in order, as well as to have them Figure l isa plan of the machine embodying the invention.

Fig. 2 is a side elevation thereof.

Fig. 3 is a plan of the corrugation-forming part of the machine, partsbeing shown in section.

Fig. 4 is a cross section of the machine on the line EE of Fig. 3.

Fig. 5 is an elevation of a part of the machine, showing the tail stockset back for the insertion of a tube to be operated upon.

' Fig. 6 is the same-showing as made'in Fig.

5, but with the tube inserted in the clutch.

Fig. 7 shows the same parts'as in F ig. 6 but with the tube partiallywithdrawnv from the cylinders, and corrugations formed on the withdrawnportion.

Fig. 8 shows the same parts, with the tube entirely withdrawn, fullycorrugated.

Fig. 9 is a longitudinal cross section of the device, showing the outerring and the inner thrust bar in co-operating position against theballs, the ring and bar being adjusted to form the corrugationssuccessively in time,

the outer corrugation being the first formed.

Fig. 9 shows the resulting form of the tube after the operation shown inFig. 9.

Fig. 10 shows the same arrangement as in Fig. 9, but with the innercorrugation formed after the outer corrugation has been formed.

Fig. 10* shows the resulting form of the tube after the operation shownin Fig. 10.

Fig. 11 shows the same arrangement as in Fig. 9 but with the balls inposition after the formation of the second outer corrugation.

Fig. 11 shows the resultant form of the tube after the operation shownin Fig. 11. i

Fig. 12 shows a different adjustment of the ring and thrust bar, wherebyan inner and an outer corrugation are formed as a couplet andsimultaneously, after an initial outer corrugation has been formed.

Fig. 12 shows the resultant shape of the tube. The operation in Fig. 12has not yet begun, butthe parts are ready to form the couplets.

i Fig. 13 shows the balls as having formed an inner and an outercorrugation simultaneous- 1y, with the same adjustment as shown in Fig.12. Y

Fig. 1'3 shows the resultant form of the tube after the operation shownin Fig. 13. Fig. 14 shows the position of the parts ready to begin theformation of a second couplet simultaneously, with the same adjustmentas shown in Fig. 12. 3

Fig. 15 shows the position of the parts after the coinpletion ofthesecond couplet of corrugations simultaneously.

Fig. 15 shows the form of the tube after the operation shown in Fig. 15.

Fig. 16 shows an arrangement in which the inner corrugation'is formedbeforethe formation of the-outer corrugation.

Fig.16 shows the form of tube after the operation-shown in Fig. 16.

Fig. 17 shows an arrangement in which the tube has been formed with theinner corrugations formed first in line as well as first in time.

Fig. 18 shows an arrangement in which there are no outer balls, theinner balls showing a method of forming only outer corrugatioBns. 3'-tube.

Fig. 19 shows an arrangement in which only inner corrugations areformed.

Fig. 19 shows the resultant form of tube.

Fig. 20 is diagrammatic, showing where the temper and toughness isplaced in the forming of the outer corrugation.

18" shows the resultant form of the Fig." 21 shows where the temper isplaced.

in both the'inn'er and outer corrugation, and the overlapping of thetemper on each face at the dividing line between the connectingcorrugations. Fig. 22 is a detail showing the manner in which the doublecammed head of the thrust bar can revolve in the end of the bar.

Figs. 23 and 2 1 (Sheet 1) are details of the clutch for the tube.

Fig. 25 (Sheet- 2) is an enlarged view of the end of the tube as shownin Fig. 17, showing the inner and outer corrugations with respect to theoriginal line of the tube wall. 7

. In the drawings-the letter A designates the metal-tube upon which theoperations of the machine are conducted. The numeral 20 indicates theframe of the machine generally, 21 the head stock at the forward end ofthe frame, 22 the front and 23 rear bearings on the headstock, 24 ahollow shaft rotatable in the bearings 2223, 24- a threaded rear end ofthe shaft, upon which a clutch de-.

vice is secured, as shown in Fig. 3. Upon the hollow shaft is securedthe driving pulley 25 stepped to permit'of variations in speed of theshaft, and operated by any suitable source of power, as by belt orelectric motor. Arranged concentrically with the axis of the hollowshaft 24 and ali ned therewith and placed toward the rear end of themachine is an inner cylinder 26 and sustained at its rear end by aproper support described below. At

the rear end of the inner cylinder there is provided a hollow portion 26provided with threads for the reception of a thread d sh nk 26, the rearend of the inner cylinder being thereby supported fixedly in the tailstock of the machine, against rotation.

Formed in the walls of the inner cylinder, '26,-are-radial series ofperforations 26", the

inner-ends of such radial perforations being contracted, as at 26, thepurpose of which is to prevent the contained'balls from dropping to .theinterior of the cylinder when the machine is at rest. These radialperforations circumferentially around the inner cylinder, are alignedwith each other. in a straight line in that direction. In practice Ihavefound that I secured'very satisfactory results byhaving three ofsuch balls in the circumferentialline, equally spaced apart. It will beseen that the arrangement described permits the balls to moveradiallyoutwardly when a proper moving force is applied. 27 indicates thecorrugating balls placed within the radial perforations.

28 indicates a sl1oul fm'mod on the forward portion of the rear end ofthe inner cylinder, this being desirable to permit of the free movementof the two cylinders in making longitudinal adjustments and to give openspace between the inner wall of the outer cylinder and the outer wall ofthe inner cylinder, as illustrated in Fig. 3 at the right hand thereofon the drawing. This transverse space provides a receptacle for the rearend of the tube A when it is in its place in the machine, as shown inthe same figure.

29 is the outer'cylmder, also arranged concentrically with the axis ofthe shaft 24:, surrounding the inner cylinder, and radially spaced toleave an opening between the outer face of the inner cylinder and itsown inner face, for the insertion of the tube A and the proper operationof the contained balls in forming the desired corrugations inward andoutward. At the rear end of the outer cylinder there is provided athreaded portion 29,

whereby is provided a threaded adjustment 29 between the two cylinders,the adjustment of which places the two series of balls circumferentiallyconsidered nearer together or further apart in longitudinal relation. 30is a threaded collar mounted on the threads of the inner cylinder andsurrounding the outer cylinder, and is in the nature of a jam nut, used,after the two cylinders have been properly longitudinally adjusted, tohold the two cylinders in their" adjusted position. In the outercylinder are provided a longitudinal series of perforations 29, whichare also arranged in circumferentially aligned series, in usual practicethree such perforations e( uall s )tlCtXl circlnnferentiall ivinsatis'factory results. But in the inner and the outer cylinders thenumber of perforations,

for the accommodation of the corrugation forming elements may be variedto suit the quality of the work. The number of perforationslongitudinally along thetwo cylinders v.11! be governed by the number ofcorrugations to be formed in the tube A. But it is notessential that-thenumber of perforations circumferentially aligned be the same'in'theouter and the inner cylinders. Becausethe metal to be worked is usuallyof about .008

inch in thickness, it is desirable that the perforations in the outercylinder be not longitudinally aligned with the perforations of theinner cylinder. The outer ends of the perforations of the outer cylinderare contracted as at 29 to prevent the escape outwardly of? thecontained balls 29 due' to centrifugal force or any other cause. lrVhenproper force is applied these balls 29 are made to travel inwardly toform inwardly extending corrugations in the wall of the tube A. r

32 is the tail stock, of ordinary structure, the interior of which isprovided withthe usual connections with the frame and having the usualhand wheel 32 for operating the adjusting screw to move the stock tovarious positions on the frame. 32 indicates the interiorly threadedsocket for the screw- 0f the 32 is a socket formed in the '90 handwheel. forward end of the tail stock to receive the rear end of theshank 26 uponwhich the rear end of the inner. cylinder ismounted' as i'above described. 32 is a clamp in the tail stock for holding the shank26 infposition. 33 is a clutch secured to the front end of the drivingshaft 24: by means of the rear threaded portion 24, the clutch beingadapted to receive and hold the forward end of the tube A in fixedrelation to the shaft 24 so as to be rotated thereby. In this clutch areadjusting screws 33 for controlling the clamping action of the clutch.Interiorly of the clutelris placed a split ring or collar 33", whichisthe particular part of the clutch that grasps the forward end of tubeA and holds it firmly radially against the rear end of a shank-33 of theclutch, as shown in Fig. 24, the shank 33 being of reduced diameter,such reduced diameter leaving a shoulder 33, against which the tube Afirmlv seats longitudinally when in clutched position.

34 indicates a pair of brackets or bearings on the head stocktransversely spaced'apart,

35 are transversely spaced parallel, shifting rods longitudinallysliding in the bearings 34, 35 are threaded adjustable forwards ends ofthe rods 35, 36 is a cross bar between the forward ends of the rods 35to secure simultaneous and equal movement of the two rods when adjusted,36 is a forwardly projecting bracket or lug on the cross bar :36, 37 isa tation being caused by the rotation of the balls that is given them bythe rotation of ,the tube A. 39 is a clamping and adjusting nut topermit of the longitudinal 1(l]llStmentof the bar 39 and hold it inadjusted relation'with respect to the cross bar and the rods It will beseen that the bar 39 in whatever position it is adjusted, movessimultaneously with the rods 35, but without ad-' justing the rods 35.The rods 35 may, by reason of their arrangement at their forward ends,as shown in Fig. 1, be longitudinally adjusted with respect to the crossbar; thus a double means of longitudinally, adjusting the two rods 35and the interior rod 39, with respect to each other is provided.

Fixed upon the respectlve rear ends of the rods 35, and longitudinallyadjusted when the rods 35 are longitudinallyadjusted, and longitudinallyshifted by the operation of the lever 38, is a head 40 having opposedlugs 40 for attachment to the rear ends of the rods 35, and held intheir attached positions with the clamping nuts 41". In the periphery ofthe head 40 is a raceway 40 and upon the ball-operating ring 40 is acooperating race way 40, within which are placed ball bearing balls 40,for the usual purpose of reducing friction. Secured within the head 40is a ball operating ring 40 adapted to revolve within the head; theinner face of the ring 40 is provided with a double cammed bead'O Thisrin 40 is longitudinally shifted with the shifting of the rods 35, asabove explained, and slides along the outer face of the outer cylinder,and as it is shifted, successively comes in contact with thesuccessively adj acent balls 29", which in operation project somewhatfrom the outer face of the cylinder, and are resultantly forced radiallyinwardly against the outer face of'the tube A, and, as the tube itselfis in rapid rotation, the three balls come in simultaneous contact withthe tube and against all parts of the circumference of the tube, to formthe inwardlyprojecting corrugation. Because of the mchned or beveledsides of the. bead 40 the radial travel of the corrugating balls isgradual and puts no sudden strain on the structure of the metal; Aretaining plate 40 is placed upon the'side, of the head 40 to keep theraceways and ring 40 properly in place.

In operation, after the rods 35 and the thrust bar 39 have been properlyadjusted to operate the balls 27 and 29 successively or in couplets, asdesired, and the two cylinders have been adjusted so as to make theinner or the outer corrugation the first in order as desired, the tailstock is set rearwardly enough to permit of the insertion of the tube Ain place and to be held by the clutch, the tail stock is moved forwardlyso far that the outer and the inner cylinders encompass the tube for thefull length to which the corrugations are to extend, and the tail stockis secured to position. When this is done, the free end of v the tubeextends into the space between the inner and outer cylinders, butwithout sup port therein, softh'at it is. freeto moveforward withoutfriction as the corrugations are being formed. The'ring 4:0 will then beat the forward end of the cylinders, and the double cammed head willalso be at the forward end of and'within the tubes, and longitudinallyspaced from the ring so as to operate the balls at the desired time withrespect to the outer balls. Then the lever 38, being then at its forwardposition, is moved rearward, thus movin therods 35 and the thrust bar 39in unison, by reason of the connection with the cross bar 36, and therin r lO and the head .39 will be moved rearwar dly and successivelycome in contact with the respective series of outer and inner balls toform respectively outer and inner corrugations in successive andconnected order, to the end of the tube where the corrugations are tocease; whereupon the lever 38 is moved forwardly again to the originalposition, the tail stock is set rearwardly again, to free the end of thetube from its enclosure within the cylinders, when it is withdrawn,fully corrugated, and another tube can be inserted and the processrepeated, for convenience the power being shut off as soon as thecorrugating has been completed, to stop the rotat10n of the ,tube.

It will be apparent that the time consumed in moving the lever rearwardand back is but a fraction of a moment, and that the actual operationsof forming the corrugatmns are all,done without any stopping or handlingof the tube after it-is once inserted in the clutch; that is the actualcorrugating steps are all automatic in their nature. It will also beapparent that the corrugations are formed successively, so thatthe'metalof the tube is free to flow longitudinally toward the forming Icorrugations without having to move over a series of corrugating rolls.It is also apparent that the bends of the corrugations so formed innerand outer, areeach successively tooled by actual contact of thecorrugation formin elements with the metal, and

' are not forme by mere bending of the metal,

and thatwhile so being tooled, the lateral walls of the corrugations atthe lateral centers between the bends of the corrugations are alsotooled, as shown in Figs. 20 and 21, so that there is an equal workingof the metal throughout the full extent of the corrugations. It ls'myexperience, after many years of practice in the making of corrugatedmetallic bellows, and in corrugating tubes, that a better result issecured by having the metal subjected as nearly as possible to an equalworking, rather than to place any particular amount of work upon somespecial locations in the corrugations. The formation of the corrugationsby my invention herein set forth accomplishes this result in an almostperfect degree, and far more perfectly than in any othercorrugation-forming devices.

vIt is manifest that by the adjustments provided in the mechanismdescribed the-relative time in which the corrugationsinner and outer areformed may be varied as described, and also that either the inner or theouter corrugation may be formed first in line at the end of the tube.While I have shown the ball moving devices as being arranged in some ofthe drawings to form the outer corrugation first at the beginning of themaking of the corrugations, in practice I have found generally that Iget better results by placing the inner corrugation first in line. It isvery desirable to have all the corrugations of equal size, and unlessthe inner corrugation is first in line, the outer corrugation will workout somewhat larger than it should be. For some purposes it seems betterto have the outer corrugation first, as for the insertion of heads forsome purposes, there is less waste of material, because the outer flareof an outer corrugation can be split in the middle to form a good flangefor holdin the head.

IVhile I have shown in the embodiment of the invention herein set fortha series of balls for forming the corrugations, other formers, as discs,or other shapes of former may be equally well employed for somepurposes. Other changes might be made in other respects, as forinstance, while I have shown for illustration a hand operated lever formoving the rods 35 and the thrust bar 39 apower operated mechanism formoving the rods might be equally well employed for the purpose. It isparticularly pointed out that in the formation successively of thecorrugations, the tooling of the inner corrugation before the formationof the next succeeding corrugation gives to the tube at such a point astifi'ness that aids in keeping the tube transversely in place betterthan it could be if a space were left uncorrugated, as well in thecenter of the tube as at the beginning of the tube.

I have shown the tube as being clutched to rotate with the drivingshaft, but, while I am using the device with the tube rotating, it wouldcome within the scope of my invention to hold the tube fixed innon-rotatable position, and rotate the cylinders holding the balls, insuch case the balls being operated transversely by the longitudinallymoving operators the same as they are operated with the tube itselfrotating, as shown While I have shown the mechanism as producingcomparatively broad shallow corrugations, the device would be welladapted to form ner cylinder and its shank are made in de- I tachablesections, so that the inner tube ma be detached and removed from themachine so that no corrugations could be made to extend outwardly,whereby while the outer cylinder is left intact to perform its work; andalso that the outer cylinder may be removed from the apparatus so thatno internally extending corrugations could be made thereby, while theinner cylinder and its corrugating elements are left to make outwardlyextending corrugations. While I have'in the drawings shown thelongitudinal series of perforations in the cylinders, and consequentlyof the balls in such perforations, as being aligned, it is not necessarythat they be aligned; and in case it is desirable to form closelycontiguous inwardly extending corrugations by means of the outercorrugating elements, it would be desirable tohave such elements in suchcylinder in longitudinally staggered relation, thereby permitting oneelement to perform its work more closely to the work of the adjacentelement without side crowding of the same.

Having now described my invention what I claim is 1. In a machine forcorrugating metal tubes, the combination of a rotating shaft, means forfixedly securing the tube to the shaft, means for rotating the shaft,and mechanism for successively expanding the wall of the tube outwardlyand inwardly.

2. In a machine for corrugating metal tubes, the combination of arotating shaft,

means for fixedly securing the tube to the.

shaft, and mechanism for successively expandingthe wall of the tubeoutwardly and inwardly, the cross walls of the respective corrugationsbeing longitudinall connected with each other.

3. In a machine for annularlv corrugating metal tubes, the combinationof a holder for the tube corrugating mechanisms devices adapted totravel longitudinally within and without the tube respectively andadapted when the devices are shifted to successively operate themechanisms to form inwardly and outwardly extending corrugations in thetube, and means for shifting the devices.

4. In a machine for annularly corrugating metal tubes, the combinationof a holder for the tube, and a device for successively formingcontiguous inward and outward corrugations in the tube, and means forlongtudinally shifting the relation of the holder and the devi e withrespect to each other,

for the formation of the respective corrugations.

5. In a machine for corrugating metal tubes, the combination of a holderfiar the tube, mechanisms within and withoigt the wall of thetubeadapted to be shifted radially outwardly and inwardly respectively,to operate successivel to form outwardly and inwardly projectingcorrugations, and means for radially shifting the elements.

6. In a machine for corrugating metal tubes, the combination of a holderfor the tube, mechanisms within and without the tube adapted to beradially shifted outwardly and inwardly respectively to operatesuccessively to form outwardly projecting and inwardly projectingcorrugations respectively, the inner end of one corrugation beingcontiguously connected to the inner end of the next succeedingcorrugation.

7. In a machine for corrugating metal tubes, the combination of a holderfor the tube, elements within and without the tube when the tube is inplace adapted to move radially outwardly and inwardly respectively, anddevices arranged inwardly and outwardly of the said elements and meansfor shifting the devices longitudinally of the elements .to successivelyshift the elements radially to form outwardly and inwardly extendingcorrugations in the wall of the tube.

8. In a machine for annularly corrugating metal tubes, the combinationof a holder for the tube, means for successively expanding portions ofthe tube into contiguous outwardly and inwardly extending corrugations,mechanism for successively operating the corrugating means, saidmechanism being arranged to successively form all corrugations in thetube-by the movement of the mechanism in one direction with respect tothe tube, and means for moving the mechanism.

9. In a machine for corrugating metal tubes, the combination of a holderfor the tube, elements within and without the tube arranged inlongitudinally fixed relation with respect to each other, and means forsuccessively shifting the elements to successively form outwardly andinwardly extending corrugations in the wall of the tube.

10. In a machine for corrugating metal tubes, the combination of aholder for the tube, elements within and without the tube arranged insuccessive and alternate order, and means for successively shifting theelements to form alternate outwardly and inwardly extendingcorrugations.

11'. In a machine for corrugating metal tubes, the combination of aholder for the tube, elements Within and without the tube forsuccessively forming the tube into contiguous outwardl and inwardlyextending corrugations, and mechanism for successivel operating theinner end outer elements, sai mechanism being adapted to form all of thecorrugations by a single continuous movement of the mechanism in onedirection.

12. In a machine for corrugating metal tubes, the combination of aholder for the tube, cylinders arranged within and without the tubehaving longitudinally spaced series of circumferentially placedapertures respectively,'the inner and outer apertures thereof being inzigzag relation to each other, radially movable elements within theapertures, and mechanism for shifting the elements to form alternateoutwardly and inwardly extending trinsverse corrugations in the wall ofthe tu e.

13. In a machine for corrugating metal tubes, the combination of aholder for the tube, cylinders arranged respectively within and withoutthe tube, each having a longitudinal series of aligned circumferentiallyspaced apertures, the series of the respective cylinders alternating inzigzag relation to each other, radially movable elements in theapertures, a plunger adapted to travel longitudinally within the innercylinder to successsively move the interior series of elementsoutwardly, a ring surrounding the outer cylinder adapted to travellongitudinally thereof to successively move the outer series of elementsinwardly, and means for moving the plunger and the ring simultaneouslyto successively form alternating outwardly and inwardly extendingcontiguous transverse connected corrugations in the wall of the tube.

14. In a machine for corrugating metal tubes, the combination oflongitudinal series of elements Within and without the tube adapted tomove inwardly and outwardly respectively, devices arrangedinwardly andoutwardly of said elements, and means for shifting the devices tosuccessively operate the elements to form outwardly and inwardlyextending corrugations.

15. In a machine forannularly corrugating metal tubes, the combinationof a holder for rotating the tube, a series of longitudinally spacedcorrugating elements arranged,circumferentially outwardly of the tube,and mechanism for successively actuating the elements to form inwardlyextending corrugations in the wall of the tube.

16. In a machine for annularly corrugating metal tubes, the combinationof a holder for the tube, a series of longitudinally spaced corrugatingelements circumferentially arranged outwardly of the tube, and means foractuating the elements inwardly comprising a ring surrounding the tubeand adapted toengage .the elements in successive longitudinal order.

17. In a machine for annularly corrugating metal tubes, the combinationof an annular series of corrugating elements placed outwardly of thetube and adapted to move inwardly with respect to the tube, means foroperating the elements to form inwardly extending corrugations in thewall of the tube, and mechanism for moving the operating means.

18. In a machine for annularly corrugating metal tubes, the combinationof a shell enclosing the tube and having an annular series of spacedcircular apertures therein, balls loosely held in the apertures, a ringsurrounding the shell arranged to contact the outer portions of theballs to move them inwardly to form inwardly extending corrugations inthe wall of the tube, and mechanism for transversely moving the ring tooperate the balls.

19. In a machine for corrugating metal tubes the combination of anelement within the-tube adapted to move outwardly and form outwardlyextending corrugations, an element outwardly of the tube adapted to bemoved inwardly to form inwardly extending corrugation, longitudinallyshiftable mechanisms for operating-the elements, a common operator forshifting the mechanisms and having independent, longitudinal shiftableconnections with each of the mechanisms and means for longitudinallyshifting the operator.

20. In a machine for corrugating metal tubes the combination oflongitudinally spaced elements placed within and without the tube forforming inwardly and outwardly extending corrugations respectivelytherein,

independent longitudinally shiftable mechanisms for operating theelements, a common, longitudinal, shiftable device having an independentshiftable connection with each of said mechanisms and means for shiftingthe device, the adjustment of the mechanisms being arranged so that theelements may be made to form inner and outer corrugations successively,or simultaneously.

21. In a machine for corrugating metal tubes the combination oflongitudinal series of elements within and without the tubes, arrangedto form alternate inward and outward corrugations in the tube,mechanisms for separately operating the elements and means for adjustingthe mechanism whereby the elements will be made to successively orconcur rently form two adjoining corrugations.

22. In a machine for corrugating metal tubes, the combination of alongitudinal series of spaced corrugation-forming elements within andwithout the tube, adapted to be moved transversely to form outward andinward transverse corrugations respectively in the wall of the tube,means for transversely moving the elements, and a longitudinalconnection between the respective series for shifting the series andmaintaining their spaced relation intact.

23. In a machine for corrugating metal tubes, the combination oflongitudinal series of elements within the tube and without the tube andadapted to move transversely to form outer and inner corrugations in thewall of the tube, means for transversely moving the elements, means foradjusting the longitudinal relation of the series with respect to eachother, and means for holding the series in fixed relation after theadjustment is made.

24. In a corrugating machine for corrugating' metal tubes, thecombination of longitudinal series of longitudinally spaced elementswithin the tube and without the tube arranged in staggered relation toeach other respectively, adapted to be moved transversely to form outerand inner consecutive corrugations in the wall of the tube, means fortransversely moving the elements, a connection between the two series,and means for shifting the connection to change the longitudinalrelation between the two series.

25. In a machine for corrugating metal tubes, the combination of alongitudinalseries of longitudinally spaced independent elements withinthe tube and without the tube in staggered relation to each otherrespectively and adapted to be successively moved transversely to formouter and inner transverse corrugations in the tube, means for intheseries to form its own corrugation, a connection between thetwo series,and means in the connection for adjusting the two series longitudinallywith respect to each other.'

26. In a machine for corrugating metal tubes, the combination oflongitudinal series of longitudinally spaced independent elements withinthe tube and without the tube arranged in longitudinally spaced relationto each other and adapted to be successively moved transversely to formouter and inner transverse corrugations in the wall of the tube, holdersfor the respective series of elements to keep the elements in spacedrelation, a longitudinally adjustable connection between the holders forshifting the longitudinal relation between the respective series ofelements, means for maintaining the holders in their adjusted relation,and means for transversely and independently shifting each of theelements of each of the series to form alternate outer and innercorrugations in the tube.

27. In a machine for corrugating metal tubes, the combination oflongitudinal series of longitudinally spaced independent elements withinand without the tube adaptedto be successively moved transversely of thetube to form consecutively connected outer and inner corrugations in thetube, holders for each of the series of elements for keeping 7dependently moving each of the elements of 28. In a machine forcorrugating metal tubes, the combination of independent transverselyshiftable corrugation-forming elements within and without the tube forforming alternate inner and outer transverse corrugations in the wall ofthe tube, mechanisms for successively shifting the elements, saidmechanisms being adaptable to form couplets of inner and outercorrugations successively.

29. In a machine for corrugating metal tubes, independent transverselyshiftable corrugation-forming elements within and without the tube forforming alternate inner and outer connected corrugations in the wall ofthe tube, mechanisms for shifting said ele ments, said mechanisms beingadaptable to form the entire series of corrugations independently, or toform a plurality of corrugations simultaneously, in series.

30. In a machine for corrugating metal tubes. the combination ofcorrugation-forming elements within and without the tube adapted to formconsecutive connected inner and outer corrugations transversely of theWall of the tube by contact with the wall thereof, said elements beingformed and placed to contact both the bent ends of the corrugations andthe connecting wall between the bent ends, whereby the bent ends and theconnecting walls are substantially equally worked through the entireextent of the corrugations, and means for operating the elements,

31. In a machine for corrugating metal tubes, corrugation-formingelements placed outwardly of the tube adapted to be transversely shiftedto form transverse inwardly extending corrugations in the wall of thetube, means for supporting the tube solely beyond that portion of thetube to be corrugated, and means for operating the corrugating elements.

32. In a machine for corrugating metal tubes, the combination ofcorrugation-forming elements within and without the tube and adapted tobe moved transversely to form outer and inner transverse corrugations inthe tube, means for operating the elements, and mechanism for supportingthe tube solely beyond that part of the tube which is to be cor rugatedduring all of the corrugating operations.

33. In a machine for-corrugating metal tubes, the combination ofcorrugation-forming elements placed within and without the tube adaptedto be moved to form outer and inner transverse corrugations in the tube,holders for the elements transversely spaced from the tube, means forshifting the elements transversely of the holders to form outer andinner corrugations in the tube, and a support for the tube arranged tohold the tube spaced between the holders and away therefrom during andafter the formation of the corrugations.

34. In a'machine for corrugating metal tubes, the combination ofholdersarranged without and within the tube, each holder being providedwith corrugation-forming elements placed in spaced relation in saidholders, means for detachably connecting the two holders with eachother, such detachable connection permitting the removal of one of theholders without detaching the other holder, and independent means foroperating the elements of each holder.

35. In a machine for corrugating metal tubes, the combination of holdersarranged without and within the tube each being provided withcorrugation-f0rming elements for independently forming inner and outercorrugations respectively, means for detachably connecting the holdersto the machine, such detachable connection permitting the removal of oneof the holders without removing the other holders, and independent meansfor operating the elements of each holder, said operating means beingdetachably connected with operating power in such a way as to permitdisconnection of one of said means without disconnecting ordiscontinuing the operation of the other means.

JOB-AM A. ZIEGLER.

